It is a general requirement in aircraft construction to create passenger aircraft with window sections that have the largest possible area. However, conventionally, the window sections are bound to positions between adjacent frame elements, which due to the short distance between frame elements results in comparatively small-area window sections. While with wider frame element spacing it would be possible to arrange the window sections more flexibly and design them so that they cover a larger area, very strongly dimensioned reinforcement structures would have to surround the window sections because the window sections themselves are not structural elements. This would result in additional aircraft weight. The larger distance between frame elements would furthermore have a negative effect on the stability of the aircraft fuselage so that in order to avoid stability loss the entire backing structure would have to be modified.
In other known solutions the window sections are arranged directly on the system line of the respective frame element, and above and below the window sections the frame elements make a transition to the respective window frame. While in principle this makes it possible to produce large-area window sections, here again the window sections are bound to fixed positions. Furthermore, the production, installation and repair of these solutions are relatively expensive.
The German utility model DE 92 17 393 U1 proposes an aircraft fuselage in which the frame elements extend across the window sections. In each case the window sections are formed by a window package which on the circumference is directly integrated in the aircraft fuselage. The aircraft fuselage comprises a plastics-based laminate and is designed in a single piece with the window packages and the frame elements. In this solution in particular the integral design is critical. Furthermore, the solution is associated with a disadvantage in that the window packages are designed as structural load-bearing components, and occurring loads are introduced directly to the window packages. Thus the windows must be arranged in the regions that experience the lightest loads, and the possible positions of the windows are limited accordingly.